Progress in neutron techniques: towards improved polymer electrolyte membranes for energy devices

International audienceDesign and implementation of advanced membrane formulations for selective transport of ionsand molecular species are critical for creating the next generations of fuel cells and separationdevices. It is necessary to understand the detailed transport mechanisms over time- andlength-scales relevant to the device operation, both in laboratory models and in workingsystems under realistic operational conditions. Neutron scattering techniques includingquasi-elastic neutron scattering, reflectivity and imaging are implemented at beamline stationsat reactor and spallation source facilities worldwide. With the advent of new and improvedinstrument design, detector methodology, source characteristics and data analysis protocols,these neutron scattering techniques are emerging as a primary tool for research to design,evaluate and implement advanced membrane technologies for fuel cell and separation devices.Here we describe these techniques and their development and implementation at the ILLreactor source (Institut Laue-Langevin, Grenoble, France) and ISIS Neutron and MuonSpallation source (Harwell Science and Technology Campus, UK) as examples. We alsomention similar developments under way at other facilities worldwide, and describeapproaches such as combining optical with neutron Raman scattering and x-ray absorptionwith neutron imaging and tomography, and carrying out such experiments in specialised fuelcells designed to mimic as closely possible actual operando conditions. These experimentsand research projects will play a key role in enabling and testing new membrane formulationsfor efficient and sustainable energy production/conversion and separations technologies